Identification: This perennial plant can grow in sunny high altitude (5,000-10,000 ft) areas of Maui County. Young plants consist of a short rosette of blue-gray felt-like leaves 10-30 cm (4-12 in) long and 2-12 cm (1-5 in) wide with a rounded tip. Leaves become smaller as the plant grows taller, eventually reaching 3 m (10 ft) tall by the second year. Conspicuous flower stalk with yellow flowers.
Impacts: Common mullein can become invasive by quickly colonizing disturbed areas. It produces numerous seeds that may remain dormant in the soil for over 100 years.
Dispersal Mechanism: Common mulleinplants are dispersed over long distances in the horticulture trade and by birds. Seeds fall nearby with a secondary spread that is usually not very far from the parent plant. In Hawai‘i, it has been speculated that seeds are dispersed in mud along roads by cars and along trails by hikers. Common mullien is only known to grow in a few locations in Maui County (upcountry East Maui; see map).

Characteristics:
More information about this pest 

Common mullein look-alikes:

Telegraph weed (Heterotheca grandiflora):
Telegraph weed grows in sunny, high altitude areas of Maui County. Plants form a rosette of hairy leaves which may be confused with common mullien. Telegraph weed's leaves have pointed tips and a strong, sagey smell when crushed.

Primrose (Oenothera biennis ):
Primrose grows in sunny, high altitude areas of Maui County. Plants form a rosette of slightly hairy leaves which may be confused with common mullien. Primroses have lance-like leaves with pointed tips versus the rounded tip of the common mullien and produce large, showy flowers up to 5 cm (2 in) across.